Last week the cabinet to which a friend of mine is connected, obviously underwent the long-awaited ADSL2+ upgrade. His modem now shows being connected to an IKNS Ikanos linecard (1.0 - H2), while there was a Broadcom linecard (84.77 H4) earlier.

Allthough the new linecard in the DSLAM and his modem both support ADSL2+ his ADSL connection still runs with regular ADSL (ITU G.992.1).

Won't ADSL2+ be activated automatically? What can he do to get ADSL2+?

Hi, the River plan is limited to ADSL, and is one of the few remaining non 2+ plans in the land. Also the Ikanos cards are ADSL/2/2+/VDSL2 capable, the latter is currently not available, should be early next year.

Anyway it would be smarter if Xnet would generally activate ADSL2+ (with limited bandwidth in my mate's case) because the double frequency bandwidth of ADSL2+ over ADSL (2.2MHz instead of 1.1MHz) reduces the effect of interferences and crosstalk and so makes connections way more stable and it raises the range, so all customers get more stability and people with a line length of >6km can still be served with broadband connections.

Here in Germany all ISPs use ADSL2+ even on lines that are limited to few MBit/s because of the chosen tariff plan. Some ISPs then limit bandwidth on the DSLAM (so the modem won't sync with more than the paid bandwidth) while others limit bandwidth on their IP-network (so the modem syncs with full speed, but won't deliver more than the paid speed). But the point is they always use ADSL2+ and so they can reach more customers and all customers get more stability. This measure turned out to be economical just for the fact, that it reduces support tickets because of unstable connections.

Hi, I totally agree, this plan and its imposed modulation limit is archaic, I dont believe any other ISPs offer this (but I could be wrong), most simply upstream limit in the BRAS although there are still a number of plans that offer 128k upstream speed as a limit, which obviously does not apply to multistreamed torrent applications.

I was under the impression the ADSL1 limited plans still connects as ADSL2+ but is capped at 8Mbps. Am I wrong?

FYI. The reason why ADSL2+ has less interference is because the modem and the exchange negotiates a lower transmitting power level. The double bandwidth comes from the "2", negotiate power level comes from "+". There is also such a thing as ADSL2 (without "+") but not in NZ and probably was short lived elsewhere.

Actually that was my understanding, all Telecom ISAMs are set to 2/2+, any limitation was upstream in the BRAS. Although if I am not mistaken that has not always been the case for these plans, again I may stand corrected.

cyril7: Actually that was my understanding, all Telecom ISAMs are set to 2/2+, any limitation was upstream in the BRAS. Although if I am not mistaken that has not always been the case for these plans, again I may stand corrected.

I used to be on the Xnet stream plan (same vintage as River), and the modem would only sync at ADSL1 (approx 7600 kbps from memory). With the stream plan there was a further upstream limitation to 256kbps download.

Upon changing to Fusion (FS/FS naked), the modem sync speed immediatly jumped in to ADSL2+ territory. This suggests the plan was limited to ADSL1 at the ISAM?? This was about 8 months ago though, so things may have changed since then.

Niel: I was under the impression the ADSL1 limited plans still connects as ADSL2+ but is capped at 8Mbps. Am I wrong?

Apparently it should, but my friend's connection is still running at ADSL1.

FYI. The reason why ADSL2+ has less interference is because the modem and the exchange negotiates a lower transmitting power level. The double bandwidth comes from the "2", negotiate power level comes from "+". There is also such a thing as ADSL2 (without "+") but not in NZ and probably was short lived elsewhere.

You are right that the "L2 power mode" of ADSL2+ reduces crosstalk. But that effect is rather weak compared to the effect the double frequency bandwidth of ADSL2+ has. Actually the double frequency bandwidth does not reduce interferences, but it compensates them better because there are more alternative carriers (frequencies) available, when there's some interfering noise. That double frequency bandwidth came first with ADSL2+, as the following chart shows:

For some unknown reason here in Germany not a single ISP uses L2-mode. That's why I've seen the effect of ADSL2+ without L2-mode in dozens of cases.Btw. interferences do not only come from crosstalk, but there are also external noise sources, such as TV and radio stations, cordless and mobile phones etc., where L2-mode is rather useless.

At 3.5km from the Pakuranga exchange (in Auckland, first one that went ADSL2+) I barely get faster than ADSL1 speed anyway.

But hasn't your signal-noise-ratio improved significantly by ADSL2+? I have a friend, who had 64dB downstream attenuation (= line length ~6km) and just 384 KBit/s with ADSL1, which changed to 51db and 2 MBit/s after ADSL2+ was activated.

DjShadow: out of interest, what kind of router is being used that gives that type of info?

It's an AVM Fritz!Box Fon, probably the best router in the world when it comes to VoIP, as it has an integrated PBX for PSTN and VoIP with support for up to 10 VoIP accounts and the ability to easily set up comprehensive dialing rules. Newer models have an integrated DECT-basestation (for cordless phones) and answering machine, which can forward voicemail as WAV file by eMail, it can fruther receive faxes and also forward them as a PDF by eMail and there are a lot of other features. It's really a very handy, super stable device, which is very comfortable to configure.Here are some screenshots of my friend's Fritz!Box in NZ (still running the German firmware):

The Fritz box is indeed a nice device. Niel you can get similar output from a Broadcom (and manyother device) modem using DMT tools which uses the TR069 standard to extract similar details from your modem below is my modem.